Effect of obesity and weight reduction in hypertension.

Obesity is known to be associated with diabetes, hypertension and hyperlipidemia in the majority of the patients. There could be inaccuracy in measuring the blood pressure in obesity, therefore a cuff of sufficient size is important in blood pressure measurement. All parameters of obesity have been found to have a correlation with hypertension and it has been suggested that change in weight would cause a change in blood pressure. A weight reduction of 12 kg results in a blood pressure fall of 21/13 mm Hg. Such changes in blood pressures have been noted in untreated hypertensives. A few studies have negated the role of change in weight to have any influence on hypertension. Obesity causes a higher cardiac output and higher blood volume leading to hypertension. There may be increased intracellular sodium and reduced sodium-potassium-ATPase activity in obesity which causes increased sodium loading in hypertension. Abnormalities related to the insulin-carbohydrate metabolism and the renin-angiotensin aldosteron system have also been demonstrated in obese patients. Weight reduction also causes reduced dietary salt intake and diminished sympathetic activity. The benefits of weight reduction appear to be directly related to the amount of weight lost.